Xinjiang Oil & Gas ›› 2024, Vol. 20 ›› Issue (4): 77-86.DOI: 10.12388/j.issn.1673-2677.2024.04.010

• NEW ENERGY • Previous Articles     Next Articles

Temperature,Pressure and Phase Transition Characteristics of Supercritical CO2 Pipeline During Commissioning Replacement Process in Xinjiang Oilfield#br#

  

  1. 1.Karamay Campus,China University of Petroleum (Beijing),Karamay 834000,Xinjiang,China; 2.Xinjiang Key Laboratory of Multi-Medium Pipeline Safety Transportation,Urumqi 830011,Xinjiang,China; 3.Production Technology Research Institute,PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China; 4.Oil and Gas Storage and Transportation Company,PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China
  • Online:2024-12-05 Published:2024-12-05

新疆油田超临界二氧化碳管道投产置换过程温压及相变特性#br#

  

  1. 1.中国石油大学(北京)克拉玛依校区,新疆克拉玛依 834000; 2.新疆多介质管道安全输送重点实验室,新疆乌鲁木齐 830011; 3.中国石油新疆油田分公司采油工艺研究院,新疆克拉玛依 834000; 4.中国石油新疆油田分公司油气储运公司,新疆克拉玛依 834000
  • 通讯作者: 邢晓凯(1970-),2005年6月毕业于北京工业大学热能工程专业,教授,博导,目前从事油气管道输送工艺、多相流与地面集输等研究。(Tel)0990-6633315(E-mail)xingxk2002@cup.edu.cn
  • 作者简介:李欣泽(1987-),2022年毕业于中国科学院西北生态环境资源研究院防灾减灾工程及防护工程专业,博士,高级工程师,目前从事超临界二氧化碳长距离输送管道运行安全保障关键技术研究。(Tel)0990-6633328(E-mail)lixinze@cupk.edu.cn
  • 基金资助:

    1.新疆维吾尔自治区自然科学基金资助项目“二氧化碳管道停输再启动温压协同变化机理与安全控制理论研”(2023D01A19);

    2.新疆维吾尔自治区“天池英才”引进计划项目“超临界二氧化碳长距离输送管道运行安全保障关键技术研究”(TCYC12);

    3.新疆天山创新团队“油气高效管输技术研究与应用创新团队”项目“超临界态二氧化碳高效管输与流动安全保障理论与技术研究”(2022TSYCTD0002);

    4.新疆维吾尔自治区“一事一议”引进战略人才项目“安全高效超临界二氧化碳管道建设关键技术与应用”(XQZX20240054);

    5.中国石油新疆油田分公司科研项目“超临界二氧化碳管道瞬态输送工艺技术研究”(XQHX20220064)

Abstract:

Due to the phase characteristics of CO2,the commissioning and replacement process of supercritical CO2 pipelines is significantly different from that of crude oil and natural gas pipelines. In this paper,OLGA software was used to simulate the commissioning and replacement process of the supercritical CO2 pipeline demonstration project in Xinjiang Oilfield,and the dynamics of pressure,temperature,density,phase transition and other parameters were captured. The effects of the initial back pressure,CO2 injection massive flow of various phases in first station filling and ambient temperature on the replacement time,temperature,pressure,phase transition process and CO2 consumption were investigated. Findings indicate that in the liquid CO2 injection stage,gaseous CO2 is constantly squeezed,and the thermal movement of gaseous CO2 molecules is intensified due to pressurization,leading to concurrent increases in pressure and temperature. Consequently,the fluids at the pipeline's end transitions directly from the gaseous to the supercritical phase. Enhancing the mass flow rate of CO2 injection in each phase can expedite the replacement process. To ensure the pipeline's maximum temperature keeping below 50 ℃,the injection flow rate of CO2 in the liquid phase should be capped at 0.5 m/s. The increase in ambient temperature significantly elevates the liquefaction pressure,prompting the fluids in most pipe sections to transition directly from the gaseous to supercritical phase,which is unfavorable for phase control. Therefore,commissioning during summer is not advisable. To facilitate the assessment of the production plan,three key indexes were proposed:safety index (pipeline temperature),efficiency index (time consumption of commissioning) and economic index (CO2 consumption),with the safety index taking precedence. The research results offer valuable insights for the development of production plans for supercritical CO2 pipelines.

Key words:

supercritical CO2, pipeline transportation, commissioning, replacement, phase control, CCUS

摘要:

鉴于CO2的相特性,超临界CO2管道投产置换过程与原油、天然气管道存在显著差异。采用OLGA软件对新疆油田某超临界CO2管道示范工程的投产置换过程进行了模拟,得到投产过程中压力、温度、密度、相态转变等参数变化规律。研究了初始背压大小、首站充注各相态CO2质量流量、环境温度的变化对置换投产过程中置换时间、温度、压力、相态转化过程、CO2用量的影响。研究结果表明,在液相CO2充注阶段,气相CO2不断被顶挤,在憋压作用下气相CO2分子热运动加剧,导致在压力升高的同时温度也升高,后段管段流体由气相直接转变为超临界相;增加各相态CO2充注质量流量可缩短置换时间,为控制管道最高温度不超过50℃,液相CO2的充注流速不能超过0.5 m/s;环境温度的升高会极大提高液化压力,同时大部分管段流体较容易从气相直接转变为超临界相,不利于相态控制,不推荐在夏季进行投产。为方便投产方案评价,提出了安全指标(管道温度)、效率指标(投产用时)、经济指标(CO2用量)三大指标,其中安全指标需优先满足。研究成果可为超临界CO2输送管道投产方案的制定提供参考。

关键词:

超临界CO2, 管道输送, 投产, 置换, 相态控制, CCUS

CLC Number: